Method Of Obtaining High-Quality Products From Polyolefine Waste Material Or Polyolefines

ABSTRACT

The object of the invention is the method of production of high value products: kerosene including cosmetic kerosene, white oils, high value paraffin and purified liquid fuels from polyolefin waste material and polyolefins. According to the invention the product of the thermocatalytic decomposition of polyolefin waste material obtained in a vapour form is subjected to a fractionating condensation or full condensation followed by fractionating distillation and to a process of catalytic hydrogenation to remove the unsaturated double bonds and hydrogenation of aromatic hydrocarbons eventually present in the product. Then the prepared fractions undergo further treatment by means of distillation in order to obtain fractions corresponding with the boiling temperature limits of the following high purity final products: gasoline fraction, cosmetic kerosene, white oil fraction—that can be eventually split into narrower fractions of physicochemical properties characteristic of different grades of white oil—and the paraffin fraction used as a raw material for preparation of cosmetic paraffin and other high quality paraffin grades. Partial condensation and re-circulation of the vaporised decomposition product to the thermocatalytic reactor is advantageous for increase the content of low boiling hydrocarbons corresponding with kerosene and white oil fractions in the product of the thermocatalytic decomposition. The suitable choice of the catalyst and reaction conditions in the process of the thermocatalytic decomposition of polyolefin wastes can result in partial cyclisation of the aliphatic hydrocarbons into naphthenic or aromatic hydrocarbons which are then transformed into naphthenic hydrocarbons improving the physicochemical properties of the obtained high value products.

FIELD OF TECHNOLOGY

The subject of this invention is a method of obtaining high-qualityproducts from polyolefine waste material, or polyolefines includingkerosene, cosmetic kerosene in particular, white oils, cosmetic paraffinand other high-quality types of paraffin and aliphatic hydrocarbonswithout any content of sulphur, nitrogen and other types of organiccompounds and double bonds, that might be used, among others, ascomponents of fuels.

STATE OF THE ART

Polyolefines are used to manufacture packages, utensils, containers ofdifferent types as well as constructional materials.

So far, the well-known methods of processing polyolefine waste material,through thermal and catalytic destruction, that are carried out,depending on the catalyst used, within the temperature range between 350and 450° C. to obtain a mixture of hydrocarbon, mainly aliphatichydrocarbons of a simple or branched-chain type, which are used ascomponents of liquid fuels. The process of thermal and catalyticdestruction can be run in such a way that the liquid product obtainedcovers a wide range of hydrocarbons, of the boiling point from around70° C. up to 600° C. These hydrocarbons are partly of unsaturatedcharacter and contain a considerable number of double bonds that reduce,due to their chemical reactivity, the stability of the product and thatcause allergy, which reduces their value as components of fuels andmakes it impossible for them to be used to manufacture products of ahigher quality, including cosmetic kerosene, white oils and paraffin.

Cosmetic kerosene is a fraction composed mainly of aliphatichydrocarbons with the boiling temperature limit of ˜180-275° C. that isto meet the high requirements with respect to purity, to be deprived ofany aromatic hydrocarbons and contain only vestigial amounts ofcompounds of sulphur, nitrogen and other impurities.

White oils are oils that are composed mainly of aliphatic hydrocarbonsof a high degree of purity, boiling between the limits of 260 up to 400°C. that do not contain any aromatic hydrocarbons and contain only verysmall amounts of compounds of sulphur and nitrogen as well as otherimpurities. White oils as technical oils of a high degree of purity arewidely used in many industrial sectors as auxiliaries in technologicalprocesses, components of chemical formulations, as well as lubricatingmedium of a high degree of purity.

As medical white oils of the highest purity degree they are employed infood, pharmaceutical and cosmetic industries.

Paraffin is a mixture of high-molecule aliphatic hydrocarbons of theboiling temperature of approximately 360-600° C.

Several types of paraffin are manufactured from refining raw products,starting from paraffin mass to cosmetic paraffin that differ from oneanother in having the contents of oil and impurities the sulphur andnitrogen compounds in particular.

So far, to manufacture kerosene, including cosmetic kerosene, white oilsand paraffin, raw materials of refinery origin have been used whichrequires them to be refined in order to remove almost completely anycompounds of sulphur and nitrogen as well as aromatic and unsaturatedhydrocarbons. This takes a several-step process of hydrogenation to befollowed and selective catalysts chosen, mainly based on noble metalsthat enable far-reaching, although not complete, removal of anycompounds of sulphur and nitrogen. To obtain from refinery raw productspure aliphatic hydrocarbons, not containing sulphur and admixtures ofaromatic hydrocarbons in technical scale, is a very difficult task, ifpossible at all.

DESCRIPTION OF THE INVENTION

A method of obtaining high-quality products from polyolefine wastematerial or polyolefines according to the invention consists in theproduct of their thermal and catalytic destruction obtained in the formof vapour to be subjected to a process of fractional condensation orafter it is condensed, of fractional distillation and catalytichydrogenation of the whole product or the fractions obtained whichprocess is run until a complete or far-reaching hydrogenation of doubleand possibly triple bonds, if they are to be found in the product, isobtained so that the final product contains almost exclusively saturatedaliphatic and partially napthenic hydrocarbons to be next processed intohigh-quality products of the highest degree of purity that do notcomprise any compounds of sulphur, nitrogen and other impurities. Theseproducts are represented first of all by cosmetic kerosene, white oilsand high-quality types of paraffin, including cosmetic paraffin.

The aliphatic hydrocarbon fractions obtained after hydrogenation andremoval of double bonds or fragments of these fractions, that remainafter the fractions corresponding to cosmetic kerosene, white oil andparaffin have been isolated through distillation, may be used aspurified liquid fuel that does not contain any compounds of sulphur andnitrogen and unsaturated hydrocarbons.

In order to increase in the product of thermal and catalytic destructionthe content of lower-boiling hydrocarbons corresponding to the fractionof kerosene and white oil, it is advised to condense partly and recyclethe product obtained in the form of vapour which results in deeperdestruction and the content of hydrocarbons boiling at the temperatureabove 400° C. in the product to be confined or eliminated.

The partly condensation and recycling into the thermal and catalyticdestruction reactor heavier vapours is carried out in such a way as toincrease in the product especially the content of hydrocarbons of thecarbon content in the chain mainly within the range C₁₀ up to C₁₆ whichcorresponds to the fraction of kerosene boiling at the range from 180°C. to 275° C. or in such a way as to increase in the product the contentof hydrocarbons of the carbon content in the chain mainly within therange C₁₅ up to C₂₅ corresponding to the fraction of white oil, boilingat the temperature limits of 260° C.-400° C. In order to obtain in theproduct a significant amount of hydrocarbons of the carbon contents inthe chain above C₂₀ corresponding to the paraffin fraction boilingwithin the limit of 360° C.-600° C., the process of catalyticdestruction of polyolefines or polyolefine waste material is run withoutheavier vapours being partly condensed and recycled.

The processing of polyolefine waste material or polyolefines may becarried out in such a way as to enable it for the product to containapart from aliphatic hydrocarbons also naphthenic groups ofhydrocarbons. For this purpose, the process of thermal and catalyticdestruction of polyolefines or polyolefine waste material is run underconditions in which, e.g. by a specially selected catalyst or byreaction temperature increased a partial cyclisation of aliphatichydrocarbons takes place with naphthenic or aromatic hydrocarbons beingcreated that in the following process of hydrogenation are totallyprocessed into naphthenic hydrocarbons and besides aliphatichydrocarbons constitute a component of the cosmetic kerosene, white oiland paraffin obtained.

Products of thermal and catalytic destruction of polyolefines andpolyolefine waste material represent especially suitable raw materialfor obtaining cosmetic kerosene, while oils and high-quality paraffinproducts, including cosmetic paraffin, since they are totally deprivedof compounds of sulphur and nitrogen and possible organic and inorganicimpurities. What is necessary is to remove double bonds throughhydrogenation which is easy to be reached by using nickelic catalysts orother types of industrial catalysts available as well as by usingfractional distillation to obtain products of the required limits ofboiling temperatures.

It makes it possible to obtain products of new quality and highenvironmental value and purity which are difficult to be obtained frompetroleum raw materials.

EXAMPLES Example I

Product of thermal and catalytic destruction of polyolefine wastematerial obtained in the form of vapour is subjected to partlycondensation of higher-boiling vapours and recycling so that theobtained product is contained within the limit of the boilingtemperature 70° C. up to 400° C. and then the product vapours aresubjected to fractional condensation with the division into twofractions: the fraction boiling within the limit up to 270° C. and thefraction boiling within the limit from 270° C. up to 390° C. Thefractions are separately subjected to the process of catalytichydrogenation using a nickelic catalyst at the temperature of 160° C.under the pressure of 80 atm until double bonds are removed to thecontent below 1% which process is to be carried on a continuous basiswith the hydrogenation product obtained being checked for the content ofdouble bonds using infrared spectrometry. The fractions obtained, theboiling limits of which are changed due to the hydrogenation of dualbonds are subjected to fractional distillation in order to obtaincosmetic kerosene that boils within the boiling limits from 180° C. upto 275° C. and white oil that boils within the boiling limits from 270°C. up to 380° C. as products of the highest degree of purity that do notcontain any aromatic hydrocarbons and compounds of sulphur and nitrogen.The fraction boiling within the limits up to 180° C. is used as acomponent of fuels.

Example II

Product of thermal and catalytic destruction of polyolefine wastematerial obtained in the form of vapour is subjected to fractionalcondensation with the division of the following three fractions: thefraction boiling within the limits up to 280° C., the fraction boilingwithin the limits from 280° C. up to 380° C., and the fraction boilingabove 380° C. The fractions are separately subjected to the process ofcatalytic hydrogenation using a nickelic catalyst at the temperature of160° C. under the pressure of 80 atm until double bonds are completelyhydrogenated which process is to be carried on a continuous basis withthe hydrogenation product obtained being checked for presence of doublebonds using infrared spectrometry. The fractions obtained, the boilinglimits of which are changed due to the hydrogenation of dual bonds aresubjected to fractional distillation in order to obtain cosmetickerosene that boils within the boiling limits from 180° C. up to 275°C., white oil that boils within the boiling limits from 270° C. up to380° C. and the paraffin fraction that boils within the boiling limitsfrom 380° C. up to 620° C. as products of the highest degree of puritythat do not contain any aromatic hydrocarbons and compounds of sulphurand nitrogen and double bonds. The paraffin fraction is subjected todeoiling with the use of a press until a high-quality paraffin of thesolidification point above 50° C. and the content of oil below 2% isobtained. The fraction of the boiling temperature limit up to 180° C. isused as a component of fuels or as a solvent of a high degree of purityfor cosmetic and other purposes.

1. A method of obtaining high-quality products from polyolefine wastematerial or polyolefines such as cosmetic kerosene, white oils,high-quality types of paraffin, including cosmetic paraffin and purifiedliquid fuels, which comprises a product of thermal and catalyticdestruction of polyolefine waste material obtained in the form of vapourthat is subject to fractional condensation or after it has beencondensed to fractional distillation and catalytic hydrogenation of thewhole product or the fractions obtained which hydrogenation is carriedout until almost complete removal of double and possibly triple bondstakes place, and then the fractions obtained are subjected to furtherprocessing through fractional distillation in order to obtain a fractionthe boiling temperature limits and the degree of purity of whichcorrespond with these of kerosene, including cosmetic kerosene boilingat the limits of approximately 180-275° C., the fraction of white oilboiling at the limits of approximately 270-400° C. that can be possiblydivided into narrower fractions corresponding with respect to physicaland chemical properties, especially to viscosity and volatility, to therequirements of adequate grades of white oil and possible of theparaffin fraction which fraction is subjected to the process ofdeoiling, preferably with the use of presses, and possibly to fractionaldistillation in order to obtain cosmetic paraffin and other high-qualitytypes of paraffin.
 2. A method, according to claim 1, which comprises aprocess of catalytic destruction of polyolefine waste material orpolyolefines which is run with the use of partial condensation andrecycling of heavier vapours until a significant increase ofhydrocarbons with the contents of carbon in the chain within the rangefrom C₁₀ up to C₁₆ is reached, which hydrocarbons correspondapproximately to the fraction of cosmetic kerosene boiling at the limitsfrom 180° C. up to 275° C.
 3. A method, according to claim 1, whichcomprises a process of catalytic destruction of polyolefines orpolyolefine waste material which is run with the use of partialcondensation and recycling of heavier vapours until a significantincrease of hydrocarbons with the contents of carbon in the chain withinthe limit from C₁₅ up to C₂₅ is reached, which hydrocarbons correspondto the fraction of white oil boiling at the limits from 260° C. up to400° C.
 4. A method, according to claim 1, which comprises a process ofcatalytic destruction of polyolefines or polyolefine waste materialwhich is run without the use of partial condensation and recycling ofheavier vapours in such a way that the product contains significantamount of hydrocarbons with the content of carbon in the chain above C₂₀and then after the product is divided into fractions which arehydrogenated, the fraction the boiling limits of which fall between 350°C. up to 650° C. is used to obtain different types of paraffin of a highdegree of purity, including cosmetic paraffin, with deoiling processesbeing employed, preferably with the use of presses or other well-knownmethods or possibly with the use of the process of fractionaldistillation.
 5. A method, according to claim 1, which comprises aprocess of catalytic destruction of polyolefine waste material orpolyolefines which is run under conditions in which through a propercatalyst being selected or the reaction temperature increased, thereoccurs partial cyclisation of aliphatic hydrocarbons with naphthenic oraromatic hydrocarbons being created that in the following process ofhydrogenation are totally processed into naphthenic hydrocarbons andbesides the aliphatic hydrocarbons they represent a component of thecosmetic kerosene, white oil and paraffin obtained.